1. Field of the Invention
This invention relates to improvements in or relating to coupling devices more particularly, but not exclusively, it relates to such devices employed on a vehicle and trailer for coupling the trailer to the vehicle.
2. Description of Related Art
Problems tend to be encountered whenever trailers are coupled to vehicles, more particularly, problems are encountered in easily aligning (usually both horizontally and vertically) a coupling part on the vehicle with a coupling part positioned on the trailer, prior to locking the two coupling parts of the coupling device to one another. Often a degree of "guess-work" manoeuvering is required by the driver of the vehicle in order to position the vehicle coupling part proximate the trailer coupling part, and usually the driver of the vehicle will require assistance by a second person observing the manoeuvre and calling out guidance instructions (and assistance may also be required by a third person to help lift a heavily loaded trailer coupling). Therefore, it is believed that coupling of the trailer is effected by a somewhat "hit and miss" or "trial and error" approach which is certainly much more difficult if the driver of the vehicle does not have any assistance from a second person to lock the coupling parts of the coupling device together.